Abstract

The alteration ocurring in a sunflower oil used discontinuously to fry potatoes in 15 succesive occasions and in the oil content in fried potatoes was studied. According to the Perevalov colorimetric test, the spectrophotometric absorption and the percentage of both nonpolar triglycerides (%NPT) and nonpolar methyl esters (%NPME) the alteration increased either in the bath oil or in the extracted oil with the number of frying occasions. The refraction index increased only in the extracted oil. A higher thermoxidative alteration in the fried potato oil was assesed by all indexes with the exception of %NME. However, according to the %NPT such alteration was lower than the according to the %NPT such alteration was lower than the recomended for oil discarding suggesting a still acceptable quality of the fried potatoes.